The R<> formatting code specifies that the contained text is a replaceable item, a placeholder, or a metasyntactic variable. It is used to indicate a component of a syntax or specification that should eventually be replaced by an actual value. For example:

Typically replaceables would be rendered in fixed-width italics or with <var>...</var> tags. The font used should be the same as that used for the C<> code, unless the R<> is inside a K<> or T<> code (or the equivalent =input or =output blocks), in which case their respective fonts should be used.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.8 or, at your option, any later version of Perl 5 you may have available.